Sunbeam replacement Demineralization cartridge DC-51.

Demineralization cartridge helps reduce white dust, which is a deposit of minerals caused by use of hard water

1 cartridge per package.

For best results replace as necessary (every one to two months, or 30 to 40 fillings under normal use) or when the humidifier has not been run for an extended period of time, and clean the humidifier as described in the Use and Care Manual